"No clue what they are going to do," nickelback Grant Stuard said. "All you can do is prepare for everything." He adds: "Just work on Houston. If Houston is on point, it doesn't matter who they put out there. We're able to handle it."

The results have been mostly favorable for UH, with one exception.

Against Tech, Bowman made his second career start in place of Carter, who suffered a high-ankle sprain in the season opener. All Bowman did was throw for a Big 12 freshman record 605 yards and five touchdowns in a 63-49 victory.

Boomer made his first career start against UH, leading Tulsa to an early 10-0 lead and nine-point advantage in the fourth quarter. But the freshman struggled down the stretch with a pair of late turnovers in a 41-26 loss.

Last week, ECU coach Scottie Montgomery choose to stay with incumbent Reid Herring, who was under pressure most of the game and threw a pair of interceptions and had a fumble that was picked up for a touchdown. Ahlers replaced Herring in the second half and led the Pirates' only touchdown drives in the 42-20 loss.

And Navy?

Coach Ken Niumatalolo made an unexpected move at quarterback in last week's 24-17 loss to Temple, switching Malcolm Perry, the team's best player, to slotback and starting Garret Lewis at quarterback. Word out of Annapolis this week is Abey could be in the mix to start.

In last year's meeting in Houston, Abey started and ran the triple-option, but trailing in the fourth quarter, the Midshipmen turned to Perry and Lewis at quarterback.

"Those guys have their strengths," UH defensive coordinator Mark D'Onofrio said. "It will be a challenge whoever they have at quarterback."

Linebacker Austin Robinson credits UH's coaching staff for getting the defense ready with so much uncertainty at quarterback. In the last two games against Tulsa and East Carolina, the Cougars have forced seven turnovers, had six sacks and 20 quarterback pressures.

"It's been a lot more difficult as far as trying to prepare for one guy," Robinson said. "We prepare for anyone. We look at the depth chart. The coaches do a great job letting us know what type of player each one is. We have a good understanding going into the game."

Regardless of who is at quarterback for Navy, Robinson said the assignment is clear: "We have to stop the run."

What helps the Cougars, Stuard said, is having an athletic player, walk-on Ike Ogbogu, serving as scout-team quarterback each week in practice.

"Ike is a good all-around player," Stuard said. "he actually throws extraordinarily well. The scout team gives us better looks than we get in the game."

Midway through the season, it's not uncommon for teams to make changes, even at quarterback, either to shake things up or as a necessity due to injuries.

"You start to get to this point in the season where health is at a premium," Applewhite said. "It's hard to always have that, especially at the quarterback position."

The carousel figures to continue the rest of the season: SMU and Tulane, a pair of November opponents, currently have question marks at quarterback.

Joseph Duarte has been a sports reporter for the Houston Chronicle since August 1996. He currently covers college athletics, focusing on the University of Houston. Previously, he wrote about the Houston Astros from 1998-2002, Houston Texans from 2002-05 and the Texas Longhorns from 2005-09. He came to the Houston Chronicle as part of an internship through the Sports Journalism Institute in 1995.